There are usually two types of printing on identification cards and passports. The first type of printing involves background printing that includes reference and security information. For example, the reference information may include the issuing agency as well as numerical data. The security information may be in the form of a watermark, an encoded magnetic strip, numerical sequences, a holographic image, etc. The second type of printing includes "personalized data" or "variable information" such as photographic, fingerprint, signature, name, address, etc.
Personalized text and image data is placed into most current passports by printing text directly into the booklet on a data receiving page with a daisy wheel-like printer and then affixing a photograph of the passport holder to the data page. This produces a passport that is vulnerable to photo-substitution. According to many forensic experts, photo-substitution accounts for over seventy percent of the incidents of passport tampering and alteration. Recent improvements in digital printing technology offer a potential method for countering this photo-substitution threat. New digital full-color printers produce near photographic quality images and passports produced with this technology offer enhanced levels of security because the images are considerably more difficult to remove and alter as compared to the photograph counterpart.
Several means of placing the variable text and image data into the passport booklet have been proposed in the past few years. One technique is based on an insert page concept. A sheet of security paper such as that used to make currency or a special synthetic paper such as Teslin is preprinted with an appropriate passport security background. The finished sheet is die cut to the dimensions of the passport creating an insert data page. This data page is positioned into the passport and then attached to the booklet via a thermal lamination process. A security laminate, which is sewn into the booklet during the fabrication process, holds the data page in the document. While this technique does provide a method of placing the variable text and color image data into the passport, it also introduces a new point of vulnerability. The entire data page can be removed from the booklet by attacking the security laminate.